How to add additional apps in the 'share via' option?

I was wondering if there is a way I can include additional apps in the dialog box that appears when I use the 'share via' feature.

For example, I want to transfer an S Note file with text to my 'private diary' app using the 'share' option. However the list of apps that appear in the dialog box does not contain the private diary app. (Another diary app - Diaro shows up though!)

Ask the app developer (Samsung, in this case, so lots of luck) to add that kind of app to the Share menu. I don't know of any app that can change those lists. (If anyone does, please post a link - I'll install it.)